This is getting away from the electronics. But I have wondered. Why haven't two speed transmissions been allowed in more classes?

It probably has to do with track size in most places. I ran 1/8 nitro on road years ago on a very large track. Even then the track was not large enough to handle the 80mph my car was capable of but it did seem to work well for the 1/10 cars that had 2 speeds. Still this was a very large track with 12 foot wide lanes and , if memory serves correct, a 150 to 200 foot back straight.

All high performance TC systems use both brake and Throttle modulation to mitigate wheel spin.

Not true. F1 TC systems did not use brakes (illegal and too much brake heat and wear). I have also seen spark interrupt systems that had nothing to do with throttle or brake used quite effectively on oval cars (despite being illegal).

This is getting away from the electronics. But I have wondered. Why haven't two speed transmissions been allowed in more classes?

Several reasons.

1. Electric generally doesn't need it. Unlike fuel burners, electric motors make maximum torque at zero rpm, so gearing down for torque isn't needed so much. You could still get performance gains with it, but they would be smaller and largely cancelled out by the added weight and drag.

2. Most two speed systems use a one-way that would eliminate engine braking. Therefore you would need a completely separate braking system just like fuel vehicles. Do you really want to have to add a disk brake and servo to the car?

2. Most two speed systems use a one-way that would eliminate engine braking. Therefore you would need a completely separate braking system just like fuel vehicles. Do you really want to have to add a disk brake and servo to the car?

This has to be the biggest reason, who the heck would want to loose engine braking on a 1/12 pan car to have to add another servo and disc brakes.

On a high grip carpet track with a 1/12 pan if you're exceeding the cars ability to generate grip during cornering, you've just come into the corner way too hot and/or you have turned in whilst braking.

1. Electric generally doesn't need it. Unlike fuel burners, electric motors make maximum torque at zero rpm, so gearing down for torque isn't needed so much. You could still get performance gains with it, but they would be smaller and largely cancelled out by the added weight and drag.

To a point, I do know from seeing ones in electric before that could be changed from a single to dual. A dual allowed more difference in the power needed at different wheel spin. As in a one speed, a electronic motor has to compensate for both low and top end (barring where its torque is). You have to make a compromise not to either destroy the motor or not have enough top end. So the two speed allowed the different gear ratios needed at different RPMs. The car in question got the same top speed, more punch, and had longer runtimes.

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2. Most two speed systems use a one-way that would eliminate engine braking. Therefore you would need a completely separate braking system just like fuel vehicles. Do you really want to have to add a disk brake and servo to the car?

Most but not all. Not sure about the vehicle I saw before.

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3. Cost and complexity.

Where is the cut off point in complexity? I mean if you look at a modern TC and all the minute adjustments on it. Then the cost of the kits themselves. I mean I understand your point, but I also wonder if certain classes already are what you state.. complex and costly.

Personally, I think a gyro countersteer system would speed people up much more than a traction control system, but that would be more beneficial to Offroad... where I probably should have posted a gyro-specific thread except the Onroad guys seem more intelligent...

Regardless of what the gyro can do, it just adds another thing that needs to be adjusted or setup. Much better to keep things simple.

Even my M11 allows channel mixing where I can mix the steering and throttle channels such that I can overide the throttle based on my steering inputs. I tried that, it may be good for beginners but it didn't make me any faster just slower and more controlable but SLOWER!

To a point, I do know from seeing ones in electric before that could be changed from a single to dual. A dual allowed more difference in the power needed at different wheel spin. As in a one speed, a electronic motor has to compensate for both low and top end (barring where its torque is). You have to make a compromise not to either destroy the motor or not have enough top end. So the two speed allowed the different gear ratios needed at different RPMs. The car in question got the same top speed, more punch, and had longer runtimes.

Brushless doesn't need a gearbox. The dynamic timing esc is all you want, it basicly is an automatic transmision (dynamic timing). smaller pionion for the inner parts and 64 steps (gears) for acceleration and straight line speed.

For many apparently too difficult hence they rather want to have what you wrote above. (no dynamic timing only a certain fixed degrees so they have to compromise)

Im sorry I just don't see how a traction compound is a driving aid. There is no continuous on board diagnostic system that constantly corrects a drivers input. I see compounds the same as adjusting your shock oil. It is more of a tuning adjustment. As far as the warmers I could care less. A few warm up laps does the same thing. But they are not on board diagnostics and corrections like traction control and a gyro would be.

I could take or leave either one of them. I have raced with compounds and without compounds. Only time it really matters is on a spec tire on a less than ideal surface.

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